CCT/COA doesn't make any difference. Both have 3 Platforms each, Can Accommodate 24 Coach train easily. unless if you want to travel in general, most of the times people board the train from Town station itself.
SBC Bound Seshadri Express halts @ COA for atleast 10-15 minutes(Usually b/w 5 PM - 5:20 PM). if one wants to travel in general by Seshadri Express from Kakinada, then he has to purchase ticket from town station and walk from CCT-COA and then board @ COA. [Based on Personal Experience during Samaikyandhra Bandh Period July-Oct'13]
COA...
more... yard has 2 pit lines. One is fixed for 12737/38. the other one is for Seshadri,AC Exp, Bhavnagar,LTT,SNSI.